Treatment of severe pulmonary hypertension in the setting of the large patent ductus arteriosus

Patent Ductus Arteriosus: A Contemporary Perspective for the Pediatric and Adult Cardiac Care Provider

The burden of patent ductus arteriosus (PDA) continues to be significant. In view of marked differences in preterm infants versus more mature, term counterparts (viewed on a continuum with adolescent and adult patients), mechanisms regulating ductal patency, genetic contributions, clinical consequences, and diagnostic and treatment thresholds are discussed separately, when appropriate. Among both preterm infants and older children and adults, a range of hemodynamic profiles highlighting the markedly variable consequences of the PDA are provided. In most contemporary settings, transcatheter closure is preferable over surgical ligation, but data on longer-term outcomes, particularly among preterm infants, are lacking. The present review provides recommendations to identify gaps in PDA diagnosis, management, and treatment on which subsequent research can be developed. Ultimately, the combination of refined diagnostic thresholds and expanded treatment options provides the best opportunities to address the burden of PDA. Although fundamental gaps remain unanswered, the present review provides pediatric and adult cardiac care providers with a contemporary framework in PDA care to support the practice of evidence-based medicine.

The effects of ductal size on the severity of pulmonary hypertension in children with patent ductus arteriosus (PDA): a multi-center study

INTRODUCTION

Patent ductus arteriosus (PDA) is a common acyanotic heart disease that presents with variable symptoms.

OBJECTIVES

This study is therefore aimed at determining the relationship between gender, age, and size of PDA and pulmonary hypertension. This study also seeks to determine the prevalence of elevated pulmonary artery systolic pressure in children with PDA.

PATIENTS AND METHODS

A descriptive study of children with patent ductus arteriosus was carried out from 2016 to 2020 in three institutions. The data were analysed with the IBM SPSS statistics for windows, version 20 (IBM Corp, Chicago) RESULT: The mean ductal size was 3.78 (2.39) mm, with a minimum of 1.0 mm and a maximum size of 10.0 mm. The mean ductal size for males, 4.02 (2.53) mm was comparable with that of the females, 3.61 (2.28) mm (Student T-test = 0.8, 0.4). The mean pulmonary artery systolic pressure (PASP) of the patients was 43.36 (24.46) mmHg. Also the mean PASP was comparable among the males and the females, 48.37 (26.69) mmHg versus 39.63 (22.16) mmHg (Student T-test = 1.81, p = 0.07). There was no correlation between age and PASP (correlation coefficient = 0.009, p = 0.92). Sixty point two percent (60.2%) (62/103) of children with PDA had pulmonary hypertension. The proportion of males with pulmonary hypertension, 48.39% (30/62) was comparable with that of the females, 51.61% (32/62) (Chi2 = 2.05, p = 0.15) and females are 1.8 times more likely to have pulmonary hypertension as males (odds ratio 1.81, 95% CI 0.8-4.1). There was a positive correlation between ductal size and PASP (Pearson correlation coefficient = 0.26, p value = 0.007). Those with moderate and large sized duct tend to have moderate and severe pulmonary hypertension respectively and this is statistically significant. Chi2 = 17.85, p = 0.007 CONCLUSION: The prevalence of pulmonary hypertension in children with PDA is 60.2%. Moderate and large size duct presents with moderate and severe pulmonary hypertension respectively. Females are 1.8 times more likely to have pulmonary hypertension than the males.

Hemodynamic and clinical consequences of early versus delayed closure of patent ductus arteriosus in extremely low birth weight infants

OBJECTIVES

To describe changes in hemodynamics, respiratory support, and growth associated with transcatheter PDA closure (TCPC) in ELBW infants, stratified by postnatal age at treatment.

STUDY DESIGN

This is an observational study of ELBW infants who underwent TCPC at ≤4 weeks (Group-1; n = 34), 4-8 weeks (Group-2; n = 33), and >8 weeks of age (Group-3; n = 33). Hemodynamic assessment was performed during TCPC. Multivariate Cox-proportionate-hazard modeling was used to identify factors associated with respiratory severity score (RSS) > 2 for >30 days following TCPC.

RESULTS

In comparison with Group-1, Group-3 infants had higher pulmonary vascular resistance (PVRi = 3.3 vs. 1.6 WU*m²; P = 0.01), less weight gain between 4 and 8 weeks of age (16 vs. 25 g/day) and took longer to achieve RSS < 2 (median 81 vs. 20 days; P = 0.001). RSS > 2 for >30 days was associated with TCPC > 8 weeks (OR = 3.2, 95% CI: 1.75-5.8; p = 0.03) and PVRi ≥ 3 (OR = 4.5, 95% CI: 2.7-8.9; p < 0.01).

CONCLUSION

ELBW infants may benefit from PDA closure within the first 4 weeks of life in order to prevent early onset pulmonary vascular disease, promote faster growth, and for quicker weaning of ventilator and oxygen support.

Pulmonary Hypertension with Prolonged Patency of the Ductus Arteriosus in Preterm Infants

There continues to be a reluctance to close the patent ductus arteriosus (PDA) in premature infants. The debate on whether the short-term outcomes translate to a difference in long-term benefits remains. This article intends to review the pulmonary vasculature changes that can occur with a chronic hemodynamically significant PDA in a preterm infant. It also explains the rationale and decision-making involved in a diagnostic cardiac catheterization and transcatheter PDA closure in these preterm infants.

Safety and Outcomes of Transcatheter Closure of Patent Ductus Arteriosus in Children With Pulmonary Artery Hypertension

To investigate whether transcatheter device closure of patent ductus arteriosus (PDA) is safe in children with pulmonary artery hypertension, we retrospectively analyzed our experience with 33 patients who underwent the procedure from January 2000 through August 2015. Pulmonary artery hypertension was defined as a pulmonary vascular resistance index (PVRI) >3 WU · m2. All 33 children (median age, 14.5 mo; median weight, 8.1 kg) underwent successful closure device implantation and were followed up for a median of 17.2 months (interquartile range [IQR], 1.0-63.4 mo). During catheterization, the median PVRI was 4.1 WU · m2 (IQR, 3.6-5.3 WU · m2), and the median mean pulmonary artery pressure was 38.0 mmHg (IQR, 25.5-46.0 mmHg). Premature birth was associated with pulmonary vasodilator therapy at time of PDA closure ( P=0.001) but not with baseline PVRI (P=0.986). Three patients (9.1%) had device-related complications (one immediate embolization and 2 malpositions). Two of these complications involved embolization coils. Baseline pulmonary vasodilator therapy before closure was significantly associated with intensive care unit admission after closure (10/12 [83.3%] with baseline therapy vs 3/21 [14.3%] without; P <0.001). Of 11 patients receiving pulmonary vasodilators before closure and having a device in place long-term, 8 (72.7%) were weaned after closure (median, 24.0 mo [IQR, 11.0-25.0 mo]). We conclude that transcatheter PDA closure can be performed safely in many children with pulmonary artery hypertension and improve symptoms, particularly in patients born prematurely. Risk factors for adverse outcomes are multifactorial, including coil use and disease severity. Multicenter studies in larger patient populations are warranted.

Initial Experience With Patent Ductus Arteriosus Ligation in Pre-term Infants With Bidirectional Shunt Pattern

Background: Patent ductus arteriosus (PDA) with a bidirectional shunt reflects critical clinical conditions. The operability of PDA with a bidirectional shunt in pre-term infants is still not clearly clarified. This study aimed to investigate the feasibility and the outcomes of PDA ligation in pre-term infants with a bidirectional shunt PDA. Methods: All pre-term infants receiving PDA ligation between 2013 and 2019 were enrolled in this prospective study. Patients were allocated into two groups based on the shunting direction of PDA, which were the left-to-right group (group A) and the bidirectional group (group B). Clinical characteristics and pre-op comorbidities were analyzed. Intraoperative complications, post-op neurological sequelae, necrotizing enterocolitis, survival, and mortality were compared between these two groups. Results: Thirty-seven pre-term infants were enrolled (18 in group A, 19 in group B). The mean post-menstrual age at PDA surgery was 32.0 ± 1.3 and 32.8 ± 1.5 weeks, respectively. Before surgery, 44.4 and 89.5% (group A vs. B) of the patients were using invasive mechanical ventilator (p < 0.01). The requirement of high-frequency oscillatory ventilatory support was significantly higher in group B. PDA rupture-related bleeding during exposing PDA or ligating PDA occurred in four infants, and all were all in group B, including one with delayed hemothorax. Early surgical mortality within 30 days of surgery was higher in group B (0 vs. 21.1%, p < 0.05), but only one death could be attributed to the surgery, which was caused by a pain-induced pulmonary hypertension crisis. The 5-year survival was 100% in group A, and 73.7% in group B (p < 0.05). Conclusion: We did not recommend routine PDA ligation in pre-term infants with a bidirectional shunt. However, a bidirectional shunt should not be an absolute contraindication if they fulfill indications of PDA closure. Unexpected intraoperative PDA rupture and delayed hemothorax in a bidirectional shunt PDA should be carefully monitored. Aggressive post-op pain control is also warranted to avoid pulmonary hypertension crisis. The post-op early mortality rate was higher in the bidirectional group, which could be inherent to their poor pre-operative lung condition. Only one death was directly related to the surgery.

Effect of patent ductus arteriosus on pulmonary vascular disease

The hemodynamic effects of a patent ductus arteriosus (PDA) are well known including systemic hypoperfusion and volume overload on the left ventricle. This article aims to provide a review of the long-standing effect of a hemodynamically significant PDA on the pulmonary vasculature and the role of cardiac catheterization in preterm infants with a PDA and pulmonary hypertension.

Surgical management of a patent ductus arteriosus: Is this still an option?

The evolution of neonatal intensive care over the past decade has seen the role of surgical patent ductus arteriosus (PDA) ligation in preterm infants both decrease in scope and become laden with uncertainty. Associations of ligation with adverse neonatal and neurodevelopmental outcomes have rendered the ligation decision more challenging for clinicians and have been associated with a decline in surgical treatment, but these findings may be due to bias from confounding by indication in observational studies rather than a causal detrimental effect of ligation. Accordingly, ligation may still be indicated for infants with large ductal shunts and moderate-severe respiratory insufficiency in whom the prospect of timely spontaneous closure appears low. Ultimately a randomized trial of surgical ligation versus conservative management is necessary to assess the efficacy of this invasive intervention in a population of extremely preterm infants with large ductal shunts. Simultaneously, the transcatheter approach to ductal closure in the very immature infant represents an exciting therapeutic alternative but which is still in its infancy. Insights into the pathophysiology of postoperative cardiorespiratory deterioration, including the importance of left ventricular afterload, may help clinicians avoid instability and mitigate a potentially injurious aspect of surgical treatment. This review examines the evidence regarding the benefits and risks of PDA surgery in preterm neonates and provides a pathophysiology-based management paradigm to guide perioperative care in high-risk infants.

Noninvasive Echocardiographic Measures of Pulmonary Vascular Resistance in Children and Young Adults with Cardiomyopathy

BACKGROUND

Patients with cardiomyopathy (CM) are at increased risk for pulmonary hypertension (PH). Data are lacking on the use of noninvasive PH measures by echocardiography in patients with CM. The aim of this study was to evaluate the correlation between Doppler-derived echocardiographic indices and catheterization-based measurement of pulmonary vascular resistance (PVR) in children and young adults with CM.

METHODS

Imaging studies were retrospectively reviewed from pediatric patients with CM who underwent both echocardiography and cardiac catheterization within a 72-hour period. The ratio of peak tricuspid regurgitation velocity to right ventricular outflow tract velocity-time integral, the S/D ratio, and right ventricular myocardial performance index were correlated with invasive PVR. Receiver operating characteristic curves were developed to determine cutoffs for detecting PVR ≥ 6 indexed Wood units, a value associated with higher heart transplantation risk.

RESULTS

Twenty-three patients with CM (median age, 11.7 years; range, 0.5-21 years) met the criteria for analysis, the majority (n = 17 [74%]) of whom had dilated CM. Linear regression showed significant correlations between echocardiography-based ratio of peak tricuspid regurgitation velocity to right ventricular outflow tract velocity-time integral, S/D ratio, and right ventricular myocardial performance index versus invasive PVR (r = 0.84, r = 0.72, and r = 0.72, respectively, P < .001). All echocardiographic measures showed high sensitivity, specificity, and predictive values to detect PVR ≥ 6 indexed Wood units, with ratio of peak tricuspid regurgitation velocity to right ventricular outflow tract velocity-time integral demonstrating the highest area under the curve (0.958; 95% CI, 0.866-1).

CONCLUSIONS

Right-sided Doppler-derived echocardiographic indices correlate with PVR measured by cardiac catheterization in children and young adults with CM. These parameters may serve as useful adjuncts in serial assessment of right ventricular hemodynamics in this population.

Reversal of severe mitral regurgitation by device closure of a large patent ductus arteriosus in a premature infant

We report a critically ill premature infant with severe mitral valve regurgitation associated with pulmonary hypertension and a severely dilated left atrium from a large patent ductus arteriosus. The mitral valve regurgitation improved significantly with normalisation of left atrial size 4 weeks after percutaneous closure of the patent ductus arteriosus. This case highlights the potential reversibility of severe mitral valve regurgitation with treatment of an underlying cardiac shunt.

Anatomical Closure of Left-to-Right Shunts in Premature Infants with Bronchopulmonary Dysplasia and Pulmonary Hypertension: A Cautionary Tale

Closure of a systemic to pulmonary shunt in premature infants with bronchopulmonary dysplasia may be beneficial, but in the presence of pulmonary hypertension is controversial. Here, we discuss two premature infants with pulmonary hypertension who developed acute pulmonary hypertensive crisis after closure of these shunts and hence advise caution.